Genomics-Enabled Technologies for Harnessing Bioenergy Potential of Phototrophic Microorganisms
ID: 3559

Abstract: Photosynthetically-driven conversion of solar energy is one of the most attractive ways to produce renewable combustible fuels in a carbon-neutral manner. With the increasing concerns over the sustainability of crop-based biofuel economy, there is a revitalized interest in using photosynthetic microorganisms, which use solar energy, H2O, and CO2, as effective alternatives for the production of biofuels and primary biomass. A detailed understanding of the metabolic and regulatory networks utilized by photoautotrophs in response to dynamic environmental conditions will significantly improve our efforts to physiologically and genetically manipulate algae and cyanobacteria for improved productivity.

The major focus of this panel is to summarize the recent advancements in genomics-driven photoautotroph biology related to bioenergy research through the use of high-throughput approaches to obtain detailed information regarding intracellular gene expression, protein abundance, and metabolic flux. Research at the Colorado School of Mines is providing a detailed understanding of the partitioning of photosynthetic reductant into the distinct metabolic pathways that facilitate bioenergy accumulation. Results regarding transcriptomic and metabolic profiles in selected native and mutant strains of green algae will be presented. Moreover, bioprospecting efforts in saline systems, which are aimed at understanding the physiological and metabolic consequences of salt water adaptation and acclimation, will also be described.

The on-going efforts at Pacific Northwest Laboratory are taking advantage of a relatively rich body of information on the biochemistry, physiology, and genetics of photosynthetic energy conversion by integrating genomic analysis with metabolic modeling approach. Constraint-base models simulating the fundamental metabolism and identifying the main metabolic and regulatory controls are being developed for two cyanobacterial species Cyanothece sp. strain ATCC 51142 and Synechocystis PCC 6803. As a proof of principle, the potential for H2 production by direct and indirect biophotolysis is being assessed in these model cyanobacterial species. The studies are also extended other biological systems with the goal to develop a more robust in silico tool for manipulating such microorganisms to act as catalysts for solar energy conversion and will potentially allow development of a highly efficient biofuel production processes.

The research efforts at the Pennsylvania State University are focused on system-level studies of Synechococcus sp. PCC 7002, a euryhaline, unicellular cyanobacterium that presents many opportunities as a platform for metabolic engineering for biofuels production. This cyanobacterium has the fastest known doubling time and is extremely tolerant of very high light intensities. Importantly, this cyanobacterium is efficiently and naturally transformable with linear and circular DNA molecules, and homologous recombination is extremely efficient. The Synechococcus sp. PCC 7002 genome has been completely sequenced and annotated and is available in public databases. This strain naturally contains six plasmids, which have copy numbers per cell that are equal to the chromosome copy number or as much as 40 times this number. Using these plasmids, systems for genetic complementation and protein overproduction have successfully been developed for this organism. Examples of attempts to modify the metabolism of this organism will be discussed.



Moderator: Alexander Beliaev, Pacific Northwest National Laboratory (United States)

Presenter 1: Systems Biology to Probe Renewable Biofuels Production in Photosynthetic Microorganisms
Matthew Posewitz, Colorado School of Mines, (United States)  [Confirmed]

Presenter 2: Synechococcus sp. PCC 7002: A Robust and Versatile Cyanobacterial Platform for Biofuels Development 
Donald Bryant, Pennsylvania State University, (United States)  [Confirmed]

Presenter 3: Maximization of Photoautotrophic Metabolism through Constraint-Based Modeling and Cultivation Approaches 
Alexander Beliaev, Pacific Northwest National Laboratory, (United States)  [Confirmed]

Presenter 4 (if necessary): {Presenter4PresentationTitle} 
{Presenter4FirstName} {Presenter4LastName}, {Presenter4CompanyName}, ({Presenter4Country})  [{Presenter4InviteStatus}]

Panel Organizer:
Alexander Beliaev, Pacific Northwest National Laboratory, (United States)

Why should your submission should be selected for this year’s program?
The major goal of the proposed panel is to highlight the recent advancements in genomics-driven photoautotroph biology related to bioenergy research. The presenters bring extensive expertise in the areas of cyanobacterial and microalgal biology, molecular genetics, and functional genomics. Dr. Bryant is an expert on the metabolism, physiology, genetics, and genomics of chlorophototrophic bacteria. He has studied cyanobacteria since 1972, and during this time he has studied nearly all aspects of the photosynthetic apparatus of these organisms. Dr. Bryant has also contributed greatly to efforts to determine genome sequences for chlorophototrophic bacteria, including genomes of 3 cyanobacteria, 15 green sulfur bacteria, and 7 filamentous anoxygenic phototrophs. Dr. Posewitz is an Assistant Professor at the Colorado School of Mines working in the area of algal H2-production. Recently, his research has expanded into the production of lipids and carbohydrates in algae and cyanobacteriaas well as application of ‘omics’-based approaches to better understand algal physiology and metabolism. Dr. Beliaev has over 15 years of experience in microbial physiology and functional genomics. His research is aimed at developing systems-level understanding of energy metabolism in bacteria. Dr. Beliaev is a Principal Investigator for two DOE Genomics:GTL Program projects focused on understanding fundamental metabolic processes leading to production of biofuels.